Journal of the Marine Biological Association of India

Feeding dynamics and diet composition of Giant trevally (Caranx ignobilis) from the Kerala coast

Volume 66 Issue 2

Elezabeth Tomy, E. M. Abdussamad, Toji Thomas and Ashly Gopinath

doi:10.6024/jmbai.2024.66.2.2501-07

Abstract

The diet composition and feeding intensity of the Giant trevally, Caranx ignobilis, along the Kerala coast, was studied during 2018-2019. The feeding behaviour of C. ignobilis revealed that it is a highly carnivorous species having a selective feeding nature, with fish accounting for 82% of the stomach contents, followed by crustaceans (13.7%) and molluscs (2.7%). Crabs emerged as the predominant individual prey item, accounting for an Index of Relative Importance (IRI) of 29%. The Stomach Fullness Index (SFI), the Vacuity Index (VI) and the gastro-somatic index were evaluated to assess its feeding dynamics. The SFI was significantly higher in spawning months (August to December) showing a direct relationship with feeding intensity. The VI showed variation in feeding during different months with the lowest VI in October (15%) and the highest in February (80%). Generally, the VI was higher from January to July and lower from August to December. Gastro somatic index was also found to be in a positive correlation with breeding time for C. ignobilis.

Keywords

Caranx ignobilis, index of relative importance, stomach fullness Index Gastro somatic Index, vacuity index

Date : 20-12-2024